The present invention relates to a device for transporting and aligning flat articles in an article processing system, typically a mail processing system. The device redirects and realigns transported flat articles in a path from a first direction to second parallel direction.
Mail processing and insertion systems such as those applicable for use with the present invention, are typically used by organizations such as banks, insurance companies and utility companies for producing a large volume of specific mailings where the contents of each mail item are directed to a particular addressee. Also, other organizations, such as direct mailers, use inserters for producing a large volume of generic mailings where the contents of each mail item are substantially identical for each addressee. Examples of such inserter systems are the 8 series and 9 series inserter systems available from Pitney Bowes Inc. of Stamford Conn.
In many respects, the typical inserter system resembles a manufacturing assembly line. Sheets and other raw materials (other sheets, enclosures, and envelopes) enter the inserter system as inputs. A plurality of different modules in the inserter system work cooperatively to process the sheets to produce a finished mail piece. The exact configuration of each inserter system depends upon the needs of each particular customer or installation.
Typically, inserter systems prepare mail pieces by gathering collations of documents on a conveyor. The collations are then transported on the conveyor to an insertion station where they are automatically stuffed into envelopes. After being stuffed with the collations, the envelopes are removed from the insertion station for further processing. Such further processing may include automated closing and sealing the envelope flap, weighing the envelope, applying postage to the envelope, and finally sorting and stacking the envelopes.
In designing a mail processing system, as described above, it is important to take into consideration various space and ergonomic considerations. A first consideration is the size of a room for housing the inserting system. While an inserting system that has a straight processing path might often be efficient, the number and size of the processing modules might be such that the customer does not have enough room in their facility to accommodate the length in a single dimension. Accordingly, it is known in the art that it may be necessary to provide a turning module, typically at a right angle, to shorten the system""s length in any one dimension. The choice or the nature and location of the turning module may be difficult, because turning may introduce additional complexity and error into the system. It is also preferable that a turning module be made to do something useful during the turning process, and that floor space and machinery not be used solely for changing the direction of the processing path.
Another consideration in assembling a mail processing system is ergonomics. Even if a customer has room for a straight system, the distance between the beginning and the end of the system might be so great as to make it difficult for an operator to effectively attend to the whole machine. Accordingly, right angle turn modules have been found to be advantageous to create xe2x80x9cLxe2x80x9d shaped or xe2x80x9cUxe2x80x9d shaped arrangements to create a work area in which operators have easier access to all of the modules.
Another ergonomic consideration is the height of various components and transports in the system. In the modules where inserts are being fed into collations of documents, operators must have access to feeders in order to refill them and to correct jams. As such, the feeders are typically placed at a level for attendants"" hands to have easy access. As a result, the transport and collations of documents are somewhat below. At an output sorting station, stacks of finished mail pieces are sorted into bins according to zip codes and postal regulations. The sorting bins are periodically hand unloaded by operators. Thus, the bins are typically placed at hand working level. As such, collations and envelopes that are processed upstream, below hand level, must elevated before the sorting stage and sorting bins.
Current mail processing machines are often required to process up to 18,000 pieces of mail an hour, and envelopes travel at speeds as high as 100 inches per second as they are being processed. The steps of moistening and sealing the envelope flaps in particular may result in problems at those speeds. Envelopes may be moving so fast that glue on a moistened envelope flap may not have time form a seal before it is subjected to further processing. Such further processing may cause the envelope flap to reopen partially or fully before the proper sealing can occur. In addition to making the envelope unsuitable for mailing, re-opened flaps can cause jamming of the system.
At such high speeds it is also important to maintain envelopes in their appropriate orientations so that they may be properly handled when they arrive at their respective processing stations. Similarly, it is important to maintain an appropriate gap between subsequent envelopes so that they do not catch up to one another and cause jams. At higher speeds, the mail processing systems become much less tolerant of orientation and spacing errors that can result in jamming and damage to mail pieces.
The present invention provides a transport mechanism preferably for use in an inserter system as described above. In a preferred first embodiment, the transport provides a ramp that can raise the elevation of vertically oriented envelopes from a first level to a second level. During and after the elevating process, the transport operates to maintain the alignment and orientation of transported envelopes square with the direction of travel.
In this preferred first embodiment, the transport comprises sets of special nips that act to drive and orient the envelopes in the direction of travel. Each set of these nips comprises a driven roller and an idler roller. The idler roller has a toroidally shaped outer surface biased against the driven roller. The transport path of transported envelopes passes between the driven roller and the idler roller.
A first set of nips are positioned to provide a horizontal driving force on the vertically oriented envelopes. Upon entering the ramp portion of the transport path, the top and bottom edges of transported envelopes are aligned substantially parallel with the direction of travel. Immediately downstream of the first set of nips, a second set of angled ramp provides a driving force angled upwards (or downwards, as the case may be) from the horizontal transport direction.
When the envelope is under the control of the first and second sets of nips, a front portion of the envelope is being driven in the angled direction, while a rear portion continues to be driven in the horizontal direction. Because the toroidal idler nip and the driven nip grip the envelope at a relatively small point of contact, the envelope is allowed to pivot in both the first and second nips. As the envelope makes the transition between the horizontal and angled nips, the envelope gradually pivots from the horizontal position to the angled position. Thus, the first and second sets of ramp nips cooperate to drive and pivot the vertically oriented envelopes within the vertical plane of the transport path to align the top and bottom edges of the envelopes substantially parallel with an angle of the angled ramp nips.
At the end of the ramped portion of the transport, a third set of nips is also angled in the ramped direction. A forth set of nips immediately downstream from the third set of nips is angled horizontally drive the envelopes horizontally at their new elevation. The third and fourth sets of nips cooperate similarly as described above to allow the envelope to pivot from its ramped direction to its horizontal direction. Thus, the elevation of a vertically transported envelope has been changed, and the orientation of the envelope within the path of travel has been maintained.
In an alternative embodiment, utilizing the same principles as the transport for adjusting the path of a vertically oriented envelope, the path for a horizontally transported envelope can be altered in the horizontal plane. Such an arrangement could be advantageous where it is desirable to switch the registration of the envelope in the transport path from a top edge to a bottom edge of the envelope, or vice-versa. For example, an operation such as printing a postage indicia usually occurs on an envelope that is top-registered in the transport path. A downstream process, such as printing a bar-code along a bottom edge of the envelope might require that the envelopes be bottom registered. Thus the present invention could be used to alter the path of the envelopes lateral to the transport direction in order to achieve the desired shift in registration from one side of the envelope to another.